1Corundum Al2O3. Forces were calculated in the 2x2x1 supercell of the hexagonal lattice by VASP with 500eV cutoff energy and 6x6x1 k-point mesh.
2
3Dielectric constant and Born effective charge tensors were calculated with the hexagonal unit cell.
4
5The Wyckoff positions are c and e, respectively, which can be found by
6
7% phonopy -c POSCAR-unitcell --symmetry --pa=auto
8
9The band structure is plotted using seekpath by
10
11% phonopy --nac --band auto -p
12
13seekpath can be installed by "pip install seekpath".
14